/* compile: 
   gcc -o dblist dblist.c -I/usr/local/include/db -I/usr/local/ssl/include 
        -L/usr/local/lib -L/usr/local/ssl/lib -ldb -lcrypto
   GNU copyleft ariel@columbia.edu, blah blah blah...
 */
#include <db.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/time.h>
#include <fcntl.h>
#include <ctype.h>
#include <unistd.h>
#include <errno.h>
#include "x509.h"
#include "asn1.h"

#define MAXSTRLEN 4096

extern char *sys_errlist[];

char *whoami;

main(argc, argv)
int argc;
char **argv;
{

   char *dbname;

   DB  *db;
   DBT dkey,dvalue;
   int result;
   int offset=0;

   char *p;
   int ptag=0, pclass, plen;
   X509 *mycert;
   char *shortname;

   whoami=argv[0];

   if (argc!=2) {
     fprintf(stderr,"usage: %s dbname\n",whoami);
     exit(1);
   }
   dbname=argv[1];
   if ((db=dbopen(dbname,O_RDONLY,0,DB_HASH,NULL)) == NULL ) {
      fprintf(stderr,"open of db '%s' failed: '%s'\n",dbname,sys_errlist[errno]);
      exit(1);
    }
   while ((result=(db->seq(db,&dkey,&dvalue,R_NEXT))) == 0) {
      if ((dvalue.size) > 520) {
        while (offset<dvalue.size) {
          p=(char *)dvalue.data+offset-1;
          ASN1_get_object((unsigned char **)&p,(long *)&plen,&ptag,&pclass,dvalue.size);
          if (ptag==V_ASN1_SEQUENCE) { /* ok, it might be a cert then. */
             /* include length of object header junk */
             plen+=p-((char *)dvalue.data+offset-1); 
             mycert=NULL;
             p=(char *)dvalue.data+offset-1;
             d2i_X509(&mycert,(unsigned char **)&p,plen);
             if (mycert==NULL) {  /* must be garbage after all */
               offset++;
               continue;
             }
             fprintf(stdout,"offset is %d\n",offset);
             break;
	  }
          else offset++;
	}
        if (offset>0) break; /* found it, let's quit */
      }
    }
   db->close(db);
   return(0);
}